1. Field of the Invention
This invention relates to a ratchet tool, more particularly to a direction-convertible ratchet tool.
2. Description of the Related Art
A conventional ratchet hand tool, such as that disclosed in each of Taiwanese Patent Nos. 371612, 364578, 361409, 361407, and 361406, generally includes a main body, a coupling member disposed at an end of the main body and adapted to couple with a tool bit, and a pawl shiftable to engage or disengage from the coupling member to transmit a torque from the main body to the coupling member in a clockwise or counterclockwise direction or in both directions. However, since only a single pawl is disposed to engage the coupling member, the driving surface is relatively small, so that wearing of the ratchet teeth formed on the main body and slippage of the pawl may occur.
In order to overcome the drawbacks associated with the aforementioned prior art, the applicant has disclosed in U.S. Pat. Nos. 6,047,802 and 7,434,493B2, a ratchet driving mechanism which has a plurality of pawls to form at least two connection points between the main body and the coupling member so as to accommodate a large torque. However, since each pawl has an end surface which is disposed to engage both the ratchet tooth and an actuating portion of an adjusting ring, the connection area between the ratchet teeth and the pawl is decreased.